["Transactions of the Institute of British Geographers, EarlyView. ", "\nShort Abstract\nThis article provides a critical cartographic analysis of the green hydrogen (GH2) maps present within the reports of European states, lobby groups and investment bodies to examine the role of geographical knowledge in the production of low‐carbon energy frontiers. It identifies three spatio‐political strategies present within these maps which form part of a broader process that I term ‘green refrontierisation’: the assembling of low‐carbon energy frontiers atop the remnants of colonial and carbon frontiers. Through a particular focus on the Namibian case, the article's findings advance debates at the intersection of energy geographies and critical cartography by demonstrating how low‐carbon energy frontiers (re)spatialise land around a series of dynamic environmental processes rather than the subterranean resources that have historically guided geographical thinking.\n\nABSTRACT\nLand is a critical requirement of low‐carbon energy transitions, driving global land acquisitions on an unprecedented scale. Under pressure to diversify and decarbonise their energy mix, European states and investors have begun to map the ‘green hydrogen potential’ of territories on the African continent, producing powerful new visualisations of energy space. This article provides a critical cartographic analysis of the green hydrogen (GH2) maps present within the reports of European states, lobby groups and investment bodies to examine the role of geographical knowledge in the production of low‐carbon energy frontiers. It identifies three spatio‐political strategies present within these maps: spatialising hydrogen potential, territorialising hydrogen space and (re)mobilising fossil fuel infrastructure. Together, these strategies form part of a broader process that I term ‘green refrontierisation’: the assembling of low‐carbon energy frontiers atop the remnants of colonial and carbon frontiers. Through a particular focus on the Namibian case, the article's findings advance debates at the intersection of energy geographies and critical cartography by demonstrating how low‐carbon energy frontiers (re)spatialise land around a series of dynamic environmental processes rather than the subterranean resources that have historically guided geographical thinking.\n"]